Socket

Socket

About

In src/ you will find a simple implementation of the socket-based activation in socket-activation.c. The Makefile will create an image and a Docker based on this work, with port 10001 and running the script write-file.py. This script just writes the hour in /tmp/hour. If connect to socket in the docker, with a command like ncat it will write the hour on the log file.

The work of the program, is basically open a socket and listen on it. When a connection is accepted executes the order passed by arguments, imitating the job of Systemd Socket. After that the connection stays openned, but it won't read from this connection.

A simple but not optimized in bash could be:

while true
        do
                ncat -l 10001
                echo "Executing order after accept connection" & disown
        done

But the client must close the connection to permit the server to run the command. That's why it's inneficient.